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OldBeardo 20

Letting roots hang down into the tank is actually pretty good if you have an airstone or air curtain in there bubbling away. It becomes like a hybrid NFT / Bubbler pot system with the best of both worlds, a large root mass that the bubbler system gives and the constant access to nutes that the NFT system gives.

It makes the grow take a little longer but you get bigger plants in my experience.

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Tim potter 5

Of the top of my head I will add one or two notes, tricks of the trade!..

1. Put a level on your tank once its in place, undo the tray blots as mush as you can without the nut coming off, In the early stage offset your top tray to make the water run a little faster down the tray by placing a spacer at the pump end..

2. Using pipe and two 90 degree bends (right angle bends) forget the hole the pump feed tube goes through as this is where that humming comes from. Take the feed tube (needs extending) up and over the top of the root tray (over the top of the hole instead of through it) and put a 90 degree bend in the end so it sits like a bath tap. This way the pump never touch the trays.

3. Keep at least 25cm between the end of the top tray and plants. This helps avoiding roots ending up in the tank.

4. Get two cheap pond thermometers (£2.00 each), place one at the pump and one at the end of the back end of the tank.. This really helps keep a good happy medium temp for roots. Water going into the top tray might be 65f, but going down the tray it cools very quickly.

5. First plant in the tray needs to avoid being directly in front of the pump feed as it gets over watered and stressed.

GV.

My roots always grow down into the tank 20 years never bin prob I think they like it

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GreenVision 19,882

@Tim potter each to their own. Personally I didn' like roots sitting a tray of water with no oxygen. Sure it's fine and won't cause a problem. But me personally I like to prevent rather than deal with where possible.

If a grower is using additives to assure nothing can occur then I'm sure there is no need for concern.

The advice was aimed at folks new to NFT that may overlook drowned roots turning bad. Not growers with 20 years NFT growing experience.

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Tim potter 5

NFT stands for Nutrient Film Technique. It was developed in England during the 1970s as a way of giving plants' roots constant access to water, nutrients and the all-important oxygen! Plants grow in a shallow 'film' of moving nutrient solution. You can grow anything from lettuce to tomatoes and cucumbers in NFT (with the right plant supports!) and the results can be very impressive indeed. What's more, there's little or no growing media involved which can seriously cut down on your regular costs as a grower.

Here are 15 great tips for growing in NFT systems (especially NFT Gro-Tanks) - all learned through blood, sweat and tears!

NFT Gro-Tank Recirculating Hydroponics System

Dial in your growing environment! Of course, this is something that all growers need to do, but it's especially important for those using NFT. Why so? Well, no growth media around the root zone means less insulation so less protection from extremes in temperature.

As with all hydroponic growing applications, the temperature of your nutrient solution is crucial. Try to keep your nutrient solution at around 65°F for high levels of dissolved oxygen and optimum nutrient uptake.

Many NFT growers start their plants in 3" rockwool starter blocks and place these directly into the grow tray through neatly cut squares in the Correx. If you go don't this route make sure that the ridges at the bottom of the cube are in line with the nutrient flow, not perpendicular to it. Otherwise your nutrient flow will be unduly impeded.

Plants grown indoors under lights will take up water at a greater rate than they take up nutrient. Over time the EC (CF) of the solution will rise. Regularly top up your tanks with water or 50% strength nutrient solution. Keep your top up nutrient solution in a separate barrel rather than using water straight from the tap.

Maintain the pH of your nutrient solution at around 5.8 - 6.2. Check regularly as it can rise as the plants feed. It's okay to turn your pumps off for half an hour while you adjust your nutrient solution's pH and strength.

As a general rule, drain your nutrient solution and replace with a fresh batch every 7 to 10 days for optimum yields. Obviously bigger tanks can get away with less frequent changes whereas bigger plants prefer more regular fresh nutrients.

Do not let any light leak into the root zone. Ensure the holes in the Correx cover are just big enough for your plants to fit through. Cover the bases of your plants to prevent green algae forming - especially important if using rockwool cubes.

Bare roots in a nutrient film technique (NFT) system.

Thoroughly clean your tanks in between crops with a soap solution and rinse thoroughly.

Use a half strength nutrient solution to start your plants off, moving to two thirds to full dosage rate (as detailed on the bottle) after the first nutrient solution change (about 7 - 10 days after planting).

Take the opportunity to observe your plants' root growth directly by simply lifting up the Correx cover!

Make sure you completely remove plastic wrapping from rockwool cubes or remove pots if using soil or coco. This allows the roots to access more oxygen.

NFT is a bare rooted growing technique. When they start fruiting, all but the smallest of plants will need additional support, i.e. yoyo's or pea netting.

Cut lengths of spreader mat long enough to allow an overhang of a few inches from the channel into the tank. No trickling water sounds!

Look for prolific root development like this before transplanting into an NFT system.

Last but certainly not least-wait until roots are bursting out of your starter blocks before inserting them into your NFT system. This is absolutely crucial! Be patient - don't go transplanting at the first sign of roots. Use air pruning techniques to really make sure that the propagation media is full of roots before transplanting to your NFT system.